Power transmission mechanism



Dec. 11, 334. w, E. BARBER ET AL POWER TRANSMISSION MECHANISM Filed July 8, 1932 7 Sheets-Sheet 1 V MN N Na A am mi ATTORNEY Dec. M, 1934. w. E. BARBER ET AL POWER TRANSMISSION MECHANISM Filed July 8, 1932 7 Sheet s-Sheet 2 197' 7 OR/Vf Y Dec. 11, 1934. W E, BARBER El AL POWER TRANSMISSION MECHANISM Filed July 8, 1932 v 7 Sheets-Sheet 3 Lil i Iii! V 7 ,4 f: I y I 1 A. ulutl df' 36 Fig. 22. 5

1 flTTORNE) W. E. BARBER ET AL POWER TRANSMISSION MECHANISM Filed July 8; 1952 7 Sheets-Sheet 4 a'llllirllrlllllll'l'lrn INEN HTTORNEY Dec. 11, 1934. w. E. BARBER Er AL 1,983,962

POWER TRANSMISSION MECHANISM Filed July 8, 1952 7 Sheets-Sheet 5 I //Vl [/V 0X8 7 WW HTTO/P/Vf v Dec. 11, 1934. w. E. BARBER ET AL POWER TRANSMISSION MECHANISM Filed July 8, 1952 7 Sheets-Sheet 6 W. E. BARBER ET AL POWER TRANSMISSION MECHANISM Dec. 11, 1934.

Filed July 8, 1932 7 Sheeis-Sheet '7 Fig. 37.

Patented Dec. 11, 1934 PATENT OFFICE POWER TBANSMISSION MECHANISM William Edward Barber and Henry Archibald Watts, South Farnborongh, England Application July 8, 1932, Serial No. 621,496 In Great Britain July 15, 1931 Claims.

This invention relates to power transmission or remote control mechanism.

According to the invention, a power transmission member or cable flexible in all directions comprises a flexible core, a wire or the like wound on the surface of the core in the form of a continuous helix, and parts on the surface of the core interposed between the turns of the helix and of external dimensions different from the external dimensions of the helix. The projecting helix or the projecting parts form spaced projections which may serve for bearing or meshing purposes.

Further, according to the invention, a flexible power transmission member comprises a flexible shaft or core, a wire, strip or the like wound on the core so as to form a projecting screw thread or helix, and a spacing wire, strip or the like wound on the core for spacing apart the turns of the projecting screw thread or helix.

One or more wires or the like may be employed on the core to form the projecting screw thread or helix, and one or more wires or the like may be wound on the core to form the spacing means.

The projecting helix and the spacing helix surrounding the core are or may be coaxial with the core.

The projecting screw thread or helix may serve as bearing parts, or as a screw, rack, toothed or a like gear member.

The power transmission member may comprise a flexible core over which is wound a layer consisting of two or more wires, certain of the wires of the layer being of greater diameter or thickness than the others so as to form a projecting helix or screw thread, and the whole forming a flexible screw.

The power transmission member may be asso ciated with a guide whereby the transmission member may serve for transmitting positive and negative longitudinal motion or, in other words, for transmitting both tension and compression. The transmission member may serve for transmitting positive or negative longitudinal motion or rotational motion.

The core may consist of a flexible shaft or cable formed from wires' twisted together, and preferably is of the known form consisting of a bundle of centre wires laid closely in helices of relatively large pitch and one or more superposed layers of wire wound closely in helices of relatively small pitch. In this known form adjacent layers are wound in opposite directions,

the bundle of centre wires being regarded as a layer. This form of core is flexible and particularly suitable for transmitting positive and negative longitudinal movement as it is practically inextensible and incompressible. This form of 5 core is also particularly suitable for transmitting rotational motion.

The transmission member may be arranged within a tube or pipe in which the spaced projections make a sliding fit, or on a rod, or in combination with some other form of guide, and the guide may be inextensible and incompressible but bendable or flexible. The guide may be rigid.

According to other features of this invention the transmission member is arranged as a guided rack or screw with its spaced projections meshing with or engaging a toothed wheel, a nut, a screw, a clamp or other movably mounted member required to be actuated.

According to another feature of the invention the transmission member is formed with its spaced projections interrupted at intervals for intermittently engaging a movably mounted member required to be actuated.

According to another feature of the invention the transmission member with its spaced projections is arranged in the form of an endless band in an endless guide for continuously or cyclically engaging a movably mounted member required to be actuated.

According to another feature of the invention the guide for the transmission member is given a special form for cam actior or other purposes.

According to another feature of the invention the transmission member is made hollow.

According to another feature of the invention, the transmission member is constructed or arranged in composite or multiple form for purposes of strength or increasing the number of control effects which can be obtained.

Other features of the invention are hereinafter described.

The invention is illustrated, more or less diagrammatically and by way of example in the accompanying drawings, in which:-

Figs. 1 and 2 are fragmentary views at right angles to one another of one form of flexible transmission member with a projecting screw thread;

Figs. 3 and 4 are sectional general arrangement views at right angles to one another, and Fig. 5 is a section on the line 5-5 in Fig. 3 of another form of flexible transmission member with a projecting screw thread in a guide tube combined with toothed wheels;

Fig. 6 is a sectional general arrangement view of another form of flexible transmission member with a projecting screw thread in a guide tubev combined with a slider which acts as a screw member;

Fig. '7 is a fragmentary view of another form of flexible transmission member with adouble projecting screw thread in a guide tube;

Fig. 8 is a fragmentary view of another form of flexible transmission member with a projecting'screw thread in a guide tube;

Fig. 9 is a sectional general arrangement view of a flexible transmissiommember with a. projecting screw thread in a guide tube combined with a nut device;

Figs. 10 and 11 are sectional general arrangement views at right angles to one another of a flexible transmission member with a projecting screw thread in a guide tube combined with a clamping handle;

Figs. 12 and 13 are fragmentary views at right angles to one another of another form of flexible transmission member of rectangular cross-section with a projecting helix;

Figs. 14 and 15 are fragmentary views at right angles to one'another of another form of flexible transmission member with projecting parts at one side in a guide tube of elongated crosssection;

Figs. 16 and 1'7 are fragmentary views at right angles to one another of another form of flexible transmission member of composite construction with projections at opposite sides in a guide tube of elongated cross-section;

Fig. 18 is a fragmentary view of another form of flexible transmission member with a projecting screw thread and combined with anti-friction balls in a guide tube;

Fig. 19 is a fragmentary view of another form of flexible transmission member with a projecting screw thread and combined with anti-friction balls in a guide tube;

Fig. 20 is a sectional general arrangement view of a flexible transmission member with a projecting screw thread combined with anti-fric= tion balls serving as a nut in a guide tube;

Fig. 21 is a sectional general arrangement view of a flexible transmission member with a projecting screw thread secured to an end fitting;

Fig. 22 is a sectional general arrangement view of a flexible transmission member with a projecting screw thread secured to another form.

of end fitting;

Fig. 23 is a sectional general'arrangement view of a flexible transmission member with a projecting screw thread secured to another form of end fitting;

Fig. 24 is a sectional general arrangement view of a flexible transmission member with a projecting screw thread secured to another form of end fitting;

Fig. 25 is a fragmentary view of one form of hollow flexible transmission member with a projecting screw thread;

Fig. 26 is a sectional general arrangement view, Fig. 27 is a section on the line 27-27 in Fig. 26 and Fig. 28 is an end view of another form of composite or multiple flexible transmission memher with projecting screw threads and end flttings in a guide tube;

Fig. 29 is a sectional general arrangement view of a flexible transmission member with a projecting screw thread in an endless tube combined with toothed wheels;

Fig. 30 is a general arrangement view of a flexible transmission member with a projecting screw thread in a bent tube combined with toothed wheels; I

Fig. 31 is a fragmentary view of a flexible transmission member with an interrupted projecting screw thread;

Fig. 32 is a sectional general arrangement view of an endless flexible transmission member with an interrupted projecting screw thread in an endless guide tube combined with toothed wheels and contact mechanism;

Fig. 33 is a sectional general arrangement view of an endless flexible transmission member with a projecting screw thread in an endless guide tube in the form of a cam combined with a toothed wheel and a rocking lever;

Fig. 34 is a sectional general arrangement view of a flexible transmission member with a projecting screw thread in a guide tube combined with a sleeve and toothed quadrant;

Fig. 35 is a general arrangement view of a flexible transmission member with a projecting screw thread .combined with a former and toothed wheel;

Fig. 36 is a general arrangement view of two flexible transmission members with meshing projecting screw threads in guide tubes at right angles to one another;

Fig. 37 is a sectional general arrangement view and Fig. 38 is a view at right angles thereto of an endless flexible transmission member with a projecting screw thread in an endless guide tube combined with a second flexible transmission member with a projecting screw thread in a straight guide tube;

Figs. 39 and 40 are general arrangement views at right angles to one another and Fig. 41 is an enlarged fragmentary view of another form of flexible transmission member supported on a guide rod; and

Fig. 42 is a general arrangement view of a flexible transmission member with projecting teeth at one side associated with a toothed wheel.

Like reference numerals indicate similar or equivalent parts wherever repeated in the drawings.

In Figs. 1 and 2, a power transmission memher, for use within a tube or other guide member, comprises a flexible core composed of a bundle of centre wires 1 laid tightly and helically at a large pitch over which is wound an inner layer 2 of wires in helices of small pitch. The transmission member also comprises an outer layer of wires 3, 3 All the wires are of circular cross-section. The inner layer 2 consists ofa number of wires laid in the opposite direction or hand to the wires 1, and the outer layer 3, 3 consists of a number of wires laid under considerable tension in the opposite direction to the wires of the inner layer. One of the wires 3 of the outer layer is of greater diameter than the other wires 3 of the outer layer, so that the larger wire 3 forms a helix or screw thread (hereinafter generally referred to as a screw thread) projecting beyond the smaller wires 3 of the outer layer and being coaxial with the core. The smaller wires 3 serve to space apart the turns of the larger wire 3 and to flx them in position on the core 12. The screw thus produced is flexible in all directions. As shown, the outer layer consists of three wires of relaquate lubricating channel.

' a guide tube so that whenit is pushed or pulled tively small diameter and one wire of relatively large diameter. The pitch or the screw thread is substantially equal to the sum of the diameters of the four wires forming the outer layer. The open pitch of the larger wire provides an ade- In the drawings the power transmission member has been diagrammatically illustrated as consisting of centre wires 1 with a layer 2,

on which an outer layer of wires 3, 3 is wound. It is however to be understood that there may be more than one layer such as 2, as hereinbeiore referred to or thatin certain cases the layer 2 may be omitted and the layer 3,v 3 be wound directly on the centre wires'l.

In Figs. 3, 4 and 5, the power transmission member comprises a flexible core 12 of wires of circular cross-section and an outer layer 3, 3 formed by winding five wires of rectangular cross-section. The tour wires 3, which serve as spacing means are of smaller radial thickness than the remaining wire 3*, which forms a projecting screw thread.

The transmission member is applied to remote control mechanism for producing both positive and negative longitudinal motion and also rotary motion by being encased in a metal guide tube 5 of such internal diameter that the larger wire 3 of the transmission member makes a sliding fit therein. At each point where the rotary motion is to be produced, a slot 6 is provided in the tube, and the teeth '7 of a toothed wheel 8 fixed on a rotary spindle 9 project through the slot into mesh with the projecting screw thread.

There may be two or more toothed wheels 8 meshing with the projecting screw thread.

The teeth of each toothed wheel are skew teeth so as to mesh properly with the projecting screw thread. By moving the transmission member longitudinally, the screw thread serves as the teeth of a rack for rotating the toothed wheels. At the operating end, the tube 5 is clamped at 10 in a stationary bracket 11. A rod 12 provided with a handle 13 is secured to one end of the transmission member for producing longitudinal movement. The rod 12 can slide and rotate in a guide 14 in the bracket, and extends through a clamp 15, which can slide but cannot rotate in the bracket.

By tightening the clamp 15 rotation of the transmission member is prevented but longitudinal movement can take place, whereas by loosening the clamp the transmission member can be rotated. When the clamp is tightened, the transmission member may be moved longitudinally by pushing or pulling the handle 13, whereby the two toothed wheels are rotated. Alternatively the transmission member may be moved longitudinally by turning either of the toothed wheels by hand, whereby at the same time the other toothed wheel is rotated. When the clamp is loosened, the transmission member can be rotated as well as moved longitudinally whereby one toothed wheel can be set angularly with respect to the other as follows. By holding one toothed wheel against rotation and rotating the transmission member, the projecting screw thread acts as a screw and the transmission member screws between the teeth of the held toothed wheel but rotates the other toothed wheel, so allowing the latter to be set to the required angular position relatively to the held toothed wheel.

The transmission member can be arranged in its screw thread rotates or moves a toothed wheel or slider, and so that when it is held against longitudinal movement and is rotated its screw thread rotates the toothed wheel or part for fine adjustment.

In Fig. 6 a power transmission member comprises a flexible core 12 of wires of circular cross-section, and an outer layer formed by winding five wires oi circular cross-section, four of the wires 3, which serve as spacing means, being of less diameter than the remaining wire 3 which forms a projecting screw thread. The transmission member is encased in a guide tube 5 and is combined with means for operating the transmission member at a position intermediate of its ends. A slot 6 is cut in the tube, and a short tubular slider 16 is mounted around the tube. A pin or screw 17 extends from the slider through the slot and engages the projecting screw thread. The complete slider which acts as a screw member, may form an operating or operated part at an intermediate position in remote control mechanism. By moving the slider axially along the tube, the transmission member is moved longitudinally. Alternatively, by moving the transmission member longitudinally, or

rotationally and not longitudinally, the slider is moved axially along the tube.

Instead of the wires in the outer layer of the transmission member being of circular or rectangular cross-section they may be of other cross-section. There may be two or more adjacent wires of larger diameter to form the projecting member.

In Fig. 7 a power transmission member comprises a flexible core l2 of wires of circular cross-section, and an outer layer formed by winding six wires of circular cross-section, four of the wires 3, which serve as spacing means, being of less diameter than the remaining two adjacent wires 3 which form a projecting screw thread. The transmission member is encased in a guide tube 5.

Instead of spacing the turns of wire which form the projecting member by means of other wires, the latter may be replaced by a metal strip.

In Fig. 8, a power transmission member comprises a flexible core 12 of wires of circular cross-section, and a spacing helix 3 of metal strip of flat cross-section alternating with a helix 3 of wire of circular cross-section forming a projecting screw thread. The strip serves to keep the turns of the helix 3 spaced apart. The transmission member is encased in a guide tube 5.

In Fig. 9 a power transmission member comprising a flexible core 12, a helix 3 and a projecting screw thread 3 (as in Fig. 8) is encased in a guide tube 5, which is made discontinuous at an operating point between its ends. A handle or the like in the form of a nut 18 is located axially between the adjacent ends of the tube and surrounds the transmission member. The nut thread meshes with the projecting screw thread 3 and thus rotation of the nut causes longitudinal movement of the transmission member. i

In a modification, instead of a threaded nut, a rotatable collar may be employed, the rotatable collar having a pin or screw 17 (as in Fig. 6) for engaging the projecting screw thread.

In Figs. 10 and 11, a power transmission member comprising a flexible core'12, spacing means 3 and a projecting screw thread 3 (as in Fig. 8) is encased in a guide tube 5 and is combined with means for permitting the transmission member being moved longitudinally and also rotated from a point intermediate of its ends. The tube 5 is made discontinuous at the operating point, the ends being held in a stationary bridge 19. Forming a continuation of the tube 5 between its two adjacent ends is a sleeve 20, which is mounted at its ends in the bridge so as to be rotatable about its own axis. The transmission member extends through the sleeve and can be clamped between a. radial web 21 projecting from a short tubular handle 22 surrounding the sleeve, and a diametrically op-- posite radial web 23, which can be tightened or loosened by means of a set screw 24 projecting from the handle 22. The clamping parts 21, 23 extend through slots 25, 26 in the sleeve so that by reciprocating the handle 22 longitudinally-longitudinal movement is given to the transmission member. Bearing against the sleeve are two limbs 27, 28 which, by means of a screw 29 projecting from the handle and a nut 30, can be tightened on to the sleeve thereby preventing longitudinal movement. By rotating the handle 22, however, the clamping parts together with the rotatable sleeve are rotated, thereby rotating the transmission member.

Instead of forming the transmission member of circular cross-section, it may be made of other cross-section according to the purpose to which it is to be applied.

In Figs. 12 and 13, a power transmission member comprises a flexible core composed of wires 1, over which is wound an inner layer 2 of wires of circular cross-section. The transmission member also comprises spacing wires 3 of circular cross-section with a projecting helix 3 (as in Figs. 1 and 2). This form is suitable for meshing with spur wheels.

In Figs. 14 and 15, a power transmission member comprises a flexible core 12 composed of wires of circular cross-section, and an outer layer 3 of wire of square cross-section, the wire of the outer layer being looped at 3 to form spaced projecting teeth at one side of the transmission member. The transmission member is encased ina guide tube 5 of elongated crosssection.

In Figs. 16 and 17, a power transmission member comprises two flexible cores 1--2 composed of wires of circular cross-section, and an outer layer 3 of wire of square cross-section, the wire of the outer layer being looped at 3 to form spaced projecting teeth at opposite sides of the transmission member. The transmission member is encased in a guide tube 5 of elongated cross-section. In this case two superposed lay= ers 2 are shown.

For the purpose of further reducingv friction of the transmission member in the guide tube, ball bearings may be arranged to support the transmission member.

tube 5. The spacing strip is formed with holes to serve as a cage for locating balls 31, which act as bearings between the core and the tube. In Fig. 19, a power transmission member comprises a flexible core 1-2 01' wires of circular cross-section, and an outer layer formed by spacing helices 01' two wires 3, and a helix 3* of metal strip of channel cross-section forming a screw thread. The transmission member is encased in a guide tube 5. The helix 3 is' formed with holes to serve as a cage for locating balls 31 which act as bearings between the wires 3 and the tube. The helix 3 is located by having its edges fitting in between adjacent turns of the wires 3.

In Fig. 20, a power transmission member com prises a flexible core 1-2 of wires of circular cross-section, and an outer layer formed by a spacing helix 3 of metal strip alternating with a helix 3 of wire forming a projecting screw thread (as in Fig. 8). The transmission member is encased in a guide tube 5. A nut or the-equiv'-' alent is formed on the tube by a sleeve '32, which surrounds the tube'and serves to retain in position balls 33 which project through holes in the tube and mesh with the projecting screw thread, so that rotation of the flexible core causes the latter to move longitudinally.

In Fig. 21, a powe transmission member comprises a flexible core composed of wires over which are wound two superimposed inner layers 2 of closely coiled wires wound in opposite direc tions. The transmission member also comprises an outer layer of four wires, three of the wires 3 which serve as spacing means, being of smaller diameter than the fourth 3 which forms 'a projecting screw thread. The transmission member is encased in a tube 5, which is bellmouthed at the end. The transmission member is secured at the end to a cylindrical operating fitting 34. The end fitting is bored axially to different diameters so as to provide shoulders as shown. The layers 2, 3 of the transmission member are stripped off to a complementary stepped formation so that the ends of the layers abut against the shoulders. The centre 'wires I extend through the end fitting, and at the ex tremity of the end fitting remote from the tube, these wires are splayed 'out and sweated as shown at 34. This arrangement is suitable where the transmission member is used for transmitting rotary movement. Radial holes 35' are formed in the end fitting for solder to" be run in. The inner extremity of the end fitting is cut with a helical slot 36, and the projecting screw thread 3 is engaged with the slot by inserting the transmission member into the end fitting by a screwing action. The extremities of the centre wires are -splayed and sweated at 37. The part 36 is also sweated-to the part 3 In Fig. 22, a power transmission -member comprises a flexible core 1 of wires, and spacing means 3 with a projecting screw thread 3 The transmission member is encased in a tube 5, and is secured at the end to a cylindrical operating end fitting 38. In this arrangement, only the centre wires 1 extend through an axial bore in the end fitting, the wires being splayed out and sweated as at 37. In this case the layer 3, 3 is Wound directly on the centre wires 1.

In Fig. 23, a power transmission member comprises a flexible core 1-2 'of wires and spacing means 3 with a projecting screw thread 3 The transmitting member is secured at the end to a cylindrical operating end fitting 39. The centre wires 1 are passed through an axial bore in the end fitting, which has two diametrical holes through it. Steel balls 40 are inserted'into the holes, and a cylindrical sleeve 41 is passed over the end fitting so as to cause the balls to bend the centre wires 1 and secure the end fitting i i position. The sleeve is located between the e d of the outer layer 3 of wires, which is strlpggd to form a shoulder, and a nut"42,' whic is screwed on to the end fitting.

In Fig. 24 a power transmission member comprises a flexible core 1-2 of wires and spacing means 3 with a projecting screw thread 3 The transmission member is secured at the end to a cylindrical operating end fitting 43. The centre wires 1 are passed through an axial bore in the end fitting for a short distance, are then brought out to a groove along the surface, and are then passed through a second hole in the end fitting and out again asshown. A cylindrical sleeve 44 is passed over the end fitting and secured in position by screw threads 45. The centre wires 1 may be sweated to the end fitting before screwing the sleeve into position.

In Fig. 25, a power transmission member comprises a flexible core 1-2 composed of a tube, formed by a helical metalstrip ,1 over which is wound inner layers 2 of wire. The transmission member also comprises an outer layer 3 oi! wires with a projecting helix or thread 3*. An axial hole 1 therefore extends through the centre of the core. The hollow core allows of the transmitting member being mounted on a rigid or flexible rod, or on a second power transmission member for effecting a second control. The second transmissionv member may be of any suitable form.

A plurality of power transmission members may be encased within the same tube so as to be movable together or separately.

In Figs. 26 to 28, three power transmission members, each comprising a flexible core 1-2 and spacing 'means 3 with a projecting screw thread 3 are encased in a tube 5. Each transmission member is secured at one end to an end fitting or handle 46, which is guided in a separate hole through a guide plate 47, which is detachably secured at 48 to a socket 49 slidably mounted on one end of the tube. Each transmission member at the other end is secured to an end fitting 50 which extends through a separate guide 51 in a socket 52, which is fixed on the tube 5. Each transmission member extends through a nut 53, which is secured to the socket 49 at 54. The socket 49 which slides on the tube is guided by a pin and slot connection 55.

The screw threads 3 on the three power transmission members inter-mesh with one another, as shown in Figs. 26 and 27. Any one transmission member can be rotated relatively to the others, and the three transmission mem bers can be moved together longitudinally, thus providing, with three transmission members, four independent controls. The combination of the three power transmission members is adapted to transmit greater power than a single transmission membe oi the same size, and such a composite trans ission member formed of separate transmission members of standard size may be used where required, instead of employing a single transmission member of larger diameter which would not also have the advantage of providing four or more independent controls.

There may be more than three transmission members, for example seven, in the same guide tube and the transmission members may be of different diameters, for example, the centre transmission member-maybe larger diameter than the outer ones. In Fig. 29, a power transmission member with spacing means 3 and a projecting screw thread 3 is encased in an endless tube 5, which extends around two toothed wheels 56. Slots '1 are cut in the tube'to permit the teeth 01 the wheels to project into the tube and mesh with the screw thread 3 on the transmission member. The transmission member thus forms a band coupling the two wheels. The two ends of the transmission member abut against each other, but need not be joined together as in which ever direction one of the wheels is rotated to act as a driving member, thetwo ends of the transmission member keep together. The ends may,

, however, be joined together to provide for increased strength or against relative rotation about the axis of the transmission member- The transmission member may be arranged to operate a series of toothed'wheels in succession. In Fig. 30 a power transmission member with spacing means 3 and a projecting screw thread 3 is encased in a guide tube 5, in proximity to five toothed wheels 58, 59, 60, 61, 62. Slots 63 .are cut in the tube to permit the teeth of the wheels to project into the tube and mesh with the screw thread 3 on the transmission member. The transmission member is secured to a .nose piece 64 at the inner end, and to a handle 65 at the outer end, and is shown engaging with the first wheel 58. By pushing the handle further into the tube the transmission member first rotates the wheel 58; then when it reaches the wheel 59 this is brought into rotation and so on. When the transmission member meshes with all the wheels, they can be brought into action at the same time.

The transmission member may be formed with the projecting screw thread 3 interrupted at parts, so as to leave gaps. If the transmission member in Fig. 30 were so formed and the transmission member extends throughout the tube, the wheels can be brought into operation in any predetermined order. Further, if the transmission member and the tube are joined at their ends or made continuous, by driving the transmission member by means of a toothed wheel, the movement of the wheels engaging the interrupted side of the screw thread is repeated cyclically.

In Fig. 31 a power transmission member comprises a flexible core 1-2 of wires of circular cross-section, and an outer layer 3 of five wires, four of the .wires 3, which serve as spacing means, being of circular cross-section and of smaller cross-section than the fourth wire 3 which forms a projecting screw thread and is of square cross-section. The screw thread 3 is ground away at intervals, as at 66 to leave gaps as referred to in the previous paragraph.

In Fig. 32, an endless power transmission 66, and a contact member 6'7, mounted on the tube, projects through a slot 68 in the tube into engagement with the transmission member. With this arrangement as the endless transmission member is driven by rotating one of the toothed wheels at constant speed, the contact member 67 is intermittently operated at long and short intervals to close a switch 69 for signalling or other purposes, such action forming an auxiliary to the gear action between the transmission member and the wheels.

In Fig. 33, an endless power transmission member with spacing means 3 and a projecting bracketI screw thread;3 is encased in an endless tube 5 and meshed with a toothed wheel 56 on a fixed axis of rotation. The tube is bent to the form of a cam, and is slotted at 70 along its outer side; A nut-like carriage 71 is slidably mounted on the tube, and extends through the slot into engagement with the helix 3 An anti-friction wheel 72 is carried on the carriage and engages theinner face 73 of a loop at one'end of a rocking lever '74, which can pivot and slide on a fixed fulcrum 75. In this arrangement, rotation or the wheel 56 drives the transmission member and traverses the carriage along the tube, so that the required cam motion is given to the lever 74 against the action of resilient or other means (not shown) tending to keep the lever 74 in its central position.

In Fig. 34, a power transmission member with spacing means 3 and a projecting screw thread 3 is encased in a tube 5, which terminates in a bracket 75. The transmission member extends through a sleeve 76, and is secured to a part 77 of square cross-section, which permits the transmission membereto slide axially but not to rotate within the sleeve. The sleeve is rotatably mounted in the ends of the bracket, and is normally kept stationary by means of serrations 78 on the sleeve and the bracket, and a helical spring -79 acting between the sleeve and the The sleeve is slotted at 80 to permit the helix 3 to mesh with a toothed quadrant 81, which is pivoted about an axis 82 on lugs projecting from the sleeve. In this arrangement movement of the transmission member longitudinally rotates the quadrant about the axis 82, and rotation 'of the transmission member rotates the sleeve and quadrant about the axis of the sleeve. The arrangement is suitable for the headlight 83 of a motor car, longitudinal movement of the transmission member providing tipping of the headlight and rotation of the transmission member providing lateral movement of the headlight in a plane at right angles to the axis of the sleev In Fig. 35, a power transmission member with spacing means 3 and a projecting screw thread 8 is wrapped spirally around a conical former 84 as on a fusee, and the former is non-rotatably mounted on aspindle 85, which can be ro- 5 tated by a'pulley and belt 86, 87. A toothed 75 member is secured to a handle 90, and by mov wheel 88 is' slidably but non-rotatably mounted on a spindle 89 arranged parallel to a gen-- erating line of the former, so as to mesh with the screw thread. The teeth of the wheel are counter-sunk in cross-section so that they cannot over-ride the screw thread sideways. In this arrangement rotation of the former causes the wheei to slide along the spindle 89 and in ing this transmission member longitudinally, the first screw thread co-acts with the second screw thread and causes longitudinal movement of the second transmission member.

In Figs. 3'7 and 38, a straight power transmission member with spacing means 3 and a projecting screw threadi 3 is encased in a straight tube 5 and secured to a handle 91 and an endless power transmission member with spacing means 3 and a projecting screw thread 3 encased in an endless tube 5 and meshed with a toothed wheel 56 on a fixed axis is arranged adjacent to and in a plane at right angles to the straight transmission member. At the point where the two tubes 5 cross over one another, they are slotted to permit the two screw threads 3 to mesh with one another. By moving the straight transmission member longitudinally, the endless transmission member is caused to rotate the wheel.

In Figs. 39, and 41, a power transmission member comprises a flexible core of wires, over ,which is wound an outer layer 3 formed by a continuous wire combined with projecting members 92 in the form of discs. In constructing the transmission member, a disc is placed on the core at regular intervals after every seventh helix of the wire 3 is wound on. The turns of the wire 3 serve as spacing means for the dises, which are held in position between adjacent turns. Each disc is prevented from rotation on the core by the wire 3, which engages a slot 93 in the disc at the point where the wire intersects the plane of the disc. The use of an encasing tube is dispensed with by supporting the discs on a fixed guide rod 94, which can be mounted on any suitable structure by eyes 95 for screws or nails. The discs are supported on the rod by the side parts of dovetail recesses 96 embracing the guide rod.

In Fig. 42, a power transmission member comprises a flexible core of wires over which is wound an outer layer 3 formed by a continuous wire with projecting loops 3 serving as teeth at intervals at one side (as in Fig. 14). The transmission member has one end secured to a toothed wheel 97, (serving as a driving handle or driven member) by means of a clamping device 98 and extends around the wheels so that the loops 3 engage pins 99 on one faceof each wheel tooth with which the transmission member engages. The teeth of the wheel are counter-sunk in cross-section, as at 100, to locate the transmission member against sideway movement on the wheel, and both faces of the wheel teeth are engaged by the loops. This construction provides for secure locking of the transmission member to the toothed wheel and avoids the use of guide plates.

A power transmission member according to the present invention having spaced projecting helical parts, teeth or the like for use with a tube, rod or other guide member is of advantage in comparison with known forms of transmission member having closely coiled wire of one gauge at the 'surface, inter alia-in reducing the bearing friction between the transmission member and the guide tube or'other part; in facilitating the helical parts of the like being used as gear or rack teeth, as a screw, or as a worm to transmit motion toor from a coacting wheel or other part; and inproviding an adequate lubricating groove or channel.

The construction of power transmission members employing wire wound under considerable tension in helices according to this invention allows of such members being easily and cheaply manufactured and provides rigidity of construction which prevents displacement of the parts during use whilst at the same time allowing flexibility of the member as a whole to be retained.

Further, owing to the transmission member being flexible, it can be used as a curved rack, screw or worm meshing with a gear-wheel, worm-wheel or the like to increase the number of teeth or projections in use at a time and the power which can be transmitted, by wrapping the transmission member partly around the gear-wheel or the like.

What we claim and desire to secure by Letters Patent of the United States of America is:-

1. A force transmission system having a force transmitting cable composed of inner and outer layers of spirally wound wire, the outer layer including one wire of larger size than the rest to form a spaced spiral rib, force transmitting and receiving members with means to engage said spiral rib whereby rotation of one member displaces the cable longitudinally which latter in turn rotates the other member.

2. A power transmission system having a flexible transmission cable composed of inner and outer spirally wound wire layers, the outer layer including one wire of larger diameter than the rest to form a spaced spirally extending raised rib, rotatable toothed force transmitting and receiving members whose teeth engage said rib of the cable intermediate its ends, an end piece secured to one end of said cable, means associated with said end piece to prevent or allow rotary movement of the cable in addition to the longitudinal movement thereof, and a guide casing within which said cable moves.

3. A'power transmission system comprising a guide casing, a flexible cable movable both longitudinally and in a rotary direction within said casing, force transmitting means adapted to apply both of these movements to the cable, a driven device adapted to move around two different axes and including a toothed pivoted sector, a spaced spirally extending rib on said cable produced by winding two wires of difierent sizes thereon, said ribs constituting a rack to engage said toothed sector and a support for said toothed sector adapted to rotate in unison with the cable about the axis of one end thereof.

4. A power transmission system comprising a guide casing, a flexible cable within said casing including a plurality of spirally wound wire layers, the outer layer thereof having two wires of different sizes to form a spaced spirally extending rib, means for transmitting forces to said cable in the rotary and in the longitudinal directions, a squared portion at the driven'end of the cable, a 'sleeve provided with a squared aperture engaging said squared portion whereby the sleeve is driven rotatably by said cable and can slide thereon, a pivot attached to said sleeve to support the controlled member and a toothed sector associated with said controlled member and adapted to engage the spiral rib on the cable whereby longitudinal movement of the cable causes movement of the controlled member about the pivot on the sleeve.

5. A transmission system comprising a guide casing, a flexible cable movable within said casing and adapted for positive and negative longitudinal movements, said cable comprising a plurality of layers of wires wound in opposite directions, the outer layer including a wire of greater diameter than the others to form a hellcal radially extending rib for engagement by means wherewith to impart movement to and from the cable.

' WILLIAM EDWARD BARBER. HENRY ARCHIBALD WATTS. 

